Agronomy and Crop Sciences Commons^™

Origin And Evolution Of Defective Interfering Rnas Of Tomato Bushy Stunt Virus, David A. Knorr, Thomas Jack Morris

School of Biological Sciences: Faculty Publications

Viruses with defective genomes have been identified in association with virtually every major family of viruses and have been widely utilized as tools for investigating virus functions in animal cell culture systems (Perrault, 1981). It is generally thought that defective interfering viruses (DIs) arise through deletion, rearrangement, or recombination of a competent viral genome. DIs tack the ability for independent existence relying on their parental helper viruses to supply factors required for replication, maturation, and/or encapsidation (Huang and Baltimore, 1977). The interference attributed to DIs is thought to result from competition with the helper virus for factors required in trans …

Mechanisms Controlling Tolerance Of Lettuce Seed To High Temperatures At Germination And Emergence, Margaret A. Mnichowicz

Masters Theses

Lettuce (Lactuca sativa L.) seed germination is inhibited when temperatures are higher than 25-30 C. The extent of this thermodormancy is affected by both genetic and environmental factors. Lettuce seed of four seedlots of "Empire" produced in the summers and winters of two years were sown in the field in late summer and early fall at Yuma, AZ to determine stand establishment with high soil temperatures. The seedlots produced in the summer had higher percent field emergence than those produced in the winter. Also, seed of these four seedlots were germinated in petri dishes in a growth chamber at 20, …

Lupin Logic Number 6, Peter Nelson

Lupin Logic

Contents

The lupin breeders of Western Australia

Lupin varieties for 1991 by John Gladstones

Prospects for the next few years

Cucumber Mosaic Virus (CMV) testing

Prospects brighten for Koreanmarket by Rory Coffey, Grain Pool of W.A.

1989/90 Pool payments

Lupin Logic Number 5, Peter Nelson

Lupin Logic

Contents

The 1991 lupincrop starts now with high quality seed

- Why test the seed

- Are farmers using the tests?

- Sample size and cost

Currency fluctuations - efffect on equity by Trevor Lovelle, Grain Pool of WA

Elliptical Combing Motion For Harvesting Bell Peppers, J. H. Wilhoit, George A. Duncan, Larry G. Wells

Biosystems and Agricultural Engineering Faculty Publications

A new concept for mechanically harvesting bell peppers, intended specifically for multiple-pass harvesting, utilized spaced horizontal fingers combing vertically upward through plant foliage in an elliptical path alternating from both sides of the row. An apparatus based on this concept was designed and built, and harvest tests were conducted to determine the effect of two main machine operating parameters, vertical picking speed and disk angle. Harvesting performance was evaluated in terms of harvest efficiency, fruit damage, and plant damage as it related to multiple-pass harvesting. Fruit removal, both harvestable size and immature, increased significantly as vertical picking speed increased. Branch …

Lupin Logic Number 4, Peter Nelson

Lupin Logic

Contents

Lupin harvesting

- Seed for 1991

- Green radish

- Calculating harvest losses

Deacreasing lupin harvesting losses by Edward Blanchard

- Cutterbar modifications

- Improving crop flow

Stubble survey by Wes Horwood

Seminar

Production and price outlook -1990

Food for thought

Lupin Logic Number 3, Peter Nelson

Lupin Logic

Contents

Heliothis by Kevin Walden

- Life cycle

- Research

- Walden's prediction for 1990

- Monitoring

- When to spray

- Heliothis - what to spray with

Superphosphate - Not just how much, but how much? where? and with what by Ron Jarvis

- Machinery modification

1989/90 Pool payments

Soybean Chlorosis Studies On High Ph Bottomland Soils, E. J. Penas, R. A. Wiese, R. W. Elmore, G. W. Hergert, R. S. Moomaw

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Soybean varieties are different in tolerance to lime-induced chlorosis. Field trials were conducted to evaluate variety performance on soils where chlorosis in soybeans was a known problem. Thirty-six varieties out of 177 were identified as tolerant to soil conditions that cause chlorosis. Eleven varieties of these 36 were found to have the most consistent yield performance on high pH soils. Tolerant varieties must be planted at adequate densities for best performance. A seeding rate of 13.5 seeds per foot of row, the highest seeding rate employed, did not appear to maximize yield on soils where chlorosis was severe. On some …

Lupin Logic Number 2, Peter Nelson

Lupin Logic

Contents

Aphids

- Population increase

- Population decrease

- Aphid species

- Time of attack

- Damage to crop

Stubble handling seeders by Glen Riethmuller

Lupin Marketing by Rory Coffey

- Saudi Arabia

- Japan

- Lupin vs protien by-products

1989/90 Lupin Pool payments

Pesticide Use On Crops In Nebraska - 1987, Maurice Baker, Nancy Peterson, Shripat T. Kamble

Nebraska Agricultural Experiment Station: Historical Research Bulletins

This is the third and most comprehensive study of pesticide use on crops in Nebraska. The first was completed in 1978 and the second one in 1982. The first study indicated that approximately 25 million pounds (11.34 million kg) of active ingredients were used on the major crops in Nebraska. This increased to approximately 30.2 million pounds (13.7 million kg) in 1982. The USDA requires accurate information to meet their responsibilities. Thus, this survey was undertaken to determine: 1) the use of pesticides on crops, pasture and rangeland and 2) to identify pest management practices.

Toward Better Minimum Tillage For South-Coastal Sandplain Soils, W L. Crabtree

Resource management technical reports

Seventeen farmers compared their conventional cropping practices with some form of minimum tillage cropping. The minimum tilled crops yielded 21 percent less grain than the conventionally sown crops. The reasons for these decreased yields were in most cases related to inexperienced management. The minimum tilled treatments usually had very poor weed kill strategies which often resulted in large weeds at sowing, very cloddy seed-beds, and numerous insects in the young crops.

Comparative Phosphate Requirements Of Yellow Serradella (Ornithopus Compressus) Burr Medic (Medicago Polymorpha Var. Brevispina) And Subterranean Clover (Trifolium Subterraneum), Blakely Paynter

Grain and Other Field Crops Research Articles

The phosphate (P) requirements of burr medic (Medicago polymorpha) on marginally acidic, medium-textured soils and yellow serradella (Ornithopus compressus) on acidic, light-textured soils in the low rainfall (< 400 mm) wheatbelt of Western Australia are not known. The hypothesis that yellow serradella, subterranean clover (Trifolium suhrerraneum) and burr medic have the same external requirement for applied P was tested in a glasshouse trial on 2 P-deficient soils. Species were compared on an equal total seed weight and similar maturity length basis. It was found that yellow serradella required less soil applied P to achieve 90% maximum shoot production or total plant (shoots + roots) growth and had a greater curvature co-efficient from fitted Mitscherlich functions than either subterranean clover or burr medic. Burr medic was the most responsive to applied P and had the largest external requirement for applied P. These differences in external P requirements were related to differences in ability of the 3 legumes to absorb P and to transport it to their shoots and were not due to differences in internal efficiency of the shoots. Yellow serradella was able to take up more P (total plant P content) per g roots than subterranean clover, and subterranean clover more than burr medic. The same relationship applied to the translocation of absorbed P from roots to shoots.

Triazine Resistant Pigweeds In Kentucky Corn Fields, Jonathan D. Green, Michael Barett, Mike Radford

Agronomy Notes

Smooth pigweed (Amaranthus hybridus) control from atrazine and/or simazine (Princep) has been unsatisfactory in some Kentucky corn fields. Many of these fields have grown corn where one or both of these herbicides have been used continuously for several years. These two triazine herbicides, particularly atrazine, are used annually on over 90% of the corn grown in Kentucky. Other areas in the U.S. and around the world have reported. unsatisfactory control from atrazine where triazine resistant pigweed has developed.

The Effects Of Within-Row Spacings & Cultivars On The Yield Of Bush Snap Beans (Phaseolus Vulgaris L.), Timothy Hafner

Masters Theses & Specialist Projects

The effects of within-row spacings and cultivars on the yield of bush snap beans (Phaseolus vulgaris L.) were studied in two experiments. In each experiment, two cultivars and four within-row spacings (8, 15, 23 and 30 cm) were arranged in a split-plot with four replications. Spacing treatments were the whole plots and cultivars were the split plots. In 1988, the two cultivars were 'Blue Lake 274' and 'White Half Runner'. In 1989, the cultivars were 'Blue Lake 274' and 'Kentucky Wonder 125'. All rows were spaced 91 cm apart. Pods were harvested and oven dried. The data were subjected …

Lupin Logic Number 1, Peter Nelson

Lupin Logic

Contents

Welcome to the first issue of Lupin Logic

- What's it all about?

- Your help is needed

- Lupin Logic mailing list

Post-mortem on seeding

Grass weed control

Market outlook: Global: supply/demand

Market development: Human consumption update

Automated Harvesting Of Burley Tobacco Ii. Evaluation Of System Performance, Larry G. Wells, George B. Day V, Timothy D. Smith

Biosystems and Agricultural Engineering Faculty Publications

A prototype system for fully automated harvesting of burley tobacco has been developed and tested. Three years of field testing has shown that mechanical losses associated with the system were only slightly higher than via conventional methods. The system performed reliably at a sustained harvesting rate of approximately 1.4 ha/day (3.4 acre/day), while indicating that a rate of 2 ha/day (5 acre/day) should be easily achievable. The system is operated by two workers and reduces conventional labor requirement by approximately 80-85%.

Automated Harvesting Of Burley Tobacco I. System Development, Larry G. Wells, George B. Day V, Timothy D. Smith

Biosystems and Agricultural Engineering Faculty Publications

A fully automated system for harvesting and handling mature buriey tobacco has been developed. This article identifies the operations essential to this harvesting concept and describes the development of the mechanisms by which they were accomplished. The system detaches, inverts and places mature plants into portable holders for air curing under waterproof covering without requiring any manual handling of the crop. Manual labor currently required to harvest buriey tobacco would be reduced by 80-85% and the system would eliminate the drudgery associated with manual handling. The harvesting system has an approximate capacity of 1.4 to 2.0 ha/day (3.5 to 5.0 …

The Effect Of Phosphorous Placement & Rate On Phosphorus Uptake, & Growth & Yield Of Tomatoes, Christopher Thompson

Masters Theses & Specialist Projects

Research was undertaken in the summer of 1989 to determine the effect of phosphorus placement on the yield and quality of field grown tomatoes Lycopersicon esculentum. A subsequent study was undertaken in the winter of 1989 to determine the effect of phosphorus rate and placement on the early growth and phosphorus uptake of young tomatoes in the greenhouse.

The purpose of this study was to attempt to find the most efficient placement and rate of supplemental phosphorus when growing tomatoes. It has been shown that placing phosphorus in a concentrated zone in contact with plant roots results in more …

Costs Of Alternative Irrigation Systems For Vegetable Crops, G J. Luke, T C. Calder

Resource management technical reports

No abstract provided.

Response Of Soybeans To Available Potassium In Three Kentucky Soils, John H. Grove, William O. Thom, Lloyd W. Murdock, James H. Herbek

Agronomy Notes

Soybeans are produced in nearly all of Kentucky's soil physiographic regions. Soybean response to potassium (K) fertilization and soil test Kvaries with soil type and location. This variation may be associated with the wide range in soil chemical and mineralogical properties among the different regions. Of particular interest are differences in that level of soil test Kat which no further yield response to K fertilizer application would be expected. The main objective of this work was to evaluate the soil K-soybean response relationship on three different field sites where soybean yields were increased by fertilizer K. Several measures of soil …

Soil Test Potassium As An Indicator Of Tobacco Response To Band Application Of Fertilizer, J. L. Sims, Kenneth L. Wells, E. C. Schwamberger

Agronomy Notes

During the past 10 years, several studies have been conducted at Lexington on the University of Kentucky Experiment Farm to compare the effect of banding fertilizer 10 to 12 inches to each side of the row with preplant broadcast applications on growth and yield of burley tobacco. Generally, banding most of the nitrogen and potassium has led to fewer problems with salt and manganese toxicity and to improved growth during the early season. However, as compared to broadcast application, banding has had varying effects on cured leaf yields. In 'some experiments banding resulted in higher yields, in other experiments in …

Sorghum Nutritional Quality, Gebisa Ejeta, Edwin T. Mertz, Lloyd Rooney, Robert Schaffer, John M. Yohe

INTSORMIL Impacts and Bulletins

Table of Contents

Opening Session Page

Introduction, D. W. Thomas

Purpose of Conference, R. Schaffert

The Sorghum Producers Views on Sorghum Quality Improvement, L. Rooney

Importance of Sorghum on a Global Scale, B. Maunder

Relevance of International Sorghum and Millet Research to U.S. Agriculture, J. M. Yohe

Potential Use Of Ethephon To Control Lodging Of Soybeans, Larry J. Grabau, Robert C. Pearce, J. V. Konsler

Agronomy Notes

Lodging is sometimes a serious problem with soybeans in Kentucky, especially with the full season crop. However, under, excellent growing conditions, or if planting rates are too high, substantial lodging of double crop soybeans can also occur. If lodging occurs early during seed fill, it can reduce yields directly by causing poorer light use and increasing diseases. If lodging occurs late during seed fill, it will have little direct effect on yield, but may have an indirect effect by slowing down harvest and increasing harvest losses. Thus, the use of an inexpensive chemical to reduce soybean lodging is attractive. Our …

Effect Of Banded Fertilizer On Manganese Toxicity Of Burley Tobacco, J. L. Sims, Kenneth L. Wells, E. C. Greer

Agronomy Notes

Relatively large amounts (1500 to 3000 lbs per acre) of inorganic fertilizers are commonly broadcast preplant in the production of burley tobacco. Such high rates of fertilizer increase both the salt content of the soil solution and soil acidity, often causing reduced stands, manganese toxicity, plant molybdenum and calcium deficiencies, delayed growth and maturity, and reduced yield and quality of cured leaf. Manganese toxicity alone is thought to cost growers 30-40 million dollars each year from yield loss and the costs associated with growing extra acreage the following year to make up their quota¥ Improved fertilizer management systems are needed …

The Effect Of Oil Well Brines On Agricultural Fields And Water, V. P. Evangelou, M. Marsi, Kenneth L. Wells

Agronomy Notes

What is Brine and Where Does it Come From?
Brine is the salty water trapped in rock formations associated with oil and gas deposits. It consists mostly of sodium chloride but can also contain other things such as organics, bromide, some heavy metals and boron. Its source as a pollutant is usually oil stripper wells which produce less than 10 barrels of oil per day with typically a 10:1 ratio of brine to oil. Such wells are distributed throughout Kentucky and are often located on farmland. In some cases, brine rises to the land surface even where no oil wells …

Iron Fertilization Of Kentucky Bluegrass, David J. Wehner, Jean E. Haley

Office of the Dean (CAFES) Scholarship

Iron applications are sometimes used to enhance the color (darker green) of turfgrass stands even when iron is not deficient. A study was conducted to determine the feasibility of replacing a portion of the total yearly N applied to Kentucky bluegrass (Poa pratensis L.) with iron. Turfgrass response to iron chelate (Sequestrene 330) applications at 2.2 kg Fe ha^-1 in combination with three liquid-applied N sources (urea, Formolene, and FLUF) at 25 kg N ha^-1 was compared to turf response from applications of the N sources at 49 kg N ha^-1. Iron was substituted for …

Pea And Faba Bean Symbiosis With Rhizobium., J. Evans, C. Wallace, N. Dobrowolski

Experimental Summaries - Plant Research

Trial 89WH55, 89KA57, 89M26, 90A12, 90A13, 90M59, 90M60

Location: Merredin, Konnongorring, Dalwallinu, Wongan Hills, Kojonup, Avondale Research Station.

To undertake relevant field studies to establish whether there are constraints to pea and bean symbiosis, arising from management, environment or genetics, and affecting crop N accumulation and productivity.

Trial 90BA60

Using Le-mat (omethoate) insecticide and legume inoculant on seed.

Location: Badgingarra Research Station,

To measure the effect of Lemat on the nodulation and growth of medics and luceme.

Coping With Brown Spot And Root Rots Of Lupins, Mark Sweetingham

Journal of the Department of Agriculture, Western Australia, Series 4

There is increasing concern that brown spot and root diseases may limit the long term viability of lupin cultivation in close rotations in the agricultural areas of Western Australia. Research has found several useful strategies to reduce the impact of brown spot and Pleiochaeta root rot so that losses can be kept to a minimum. Rhizoctonia has proved more difficult to combat. Although less widespread than Pleiochaeta, it has caused severe losses and appears to be increasing in incidence, particularly in the northern wheatbelt. Research has vastly expanded our knowledge of the strains of Rhizoctonia present in our soils and …

Rhizoctonia Bare Patch Of Cereals And Lupins. Sterile Red Fungus (Srf) And Control Of Take-All Disease In Wheat., G. C. Macnish

Experimental Summaries - Plant Research

Trial 86E31

Rhizoctonia strains and paddock history.

Location: Esperance Downs Research Station ( Paddock C5)

To determine the effects of pasture, cultivation and cropping on Rhizoctonia root rot, Rhizoctonia patch and distribution of patch and non-patch strains of R. spp

Trial 88E39

Rhizoctonia patch mini-plot establishment area.

Location: Esperance Downs Research Station ( Paddock N1B)

To examine the effects of cultivation and minimum tillage in patches in lupins and to provide sites for mini-plot experiment.

Trial 88KO15

Rhizoctonia bare patch establishment area.

Location: Kojaneerup annex.

To establish an area (with a known history) for future research.

Trial 89E12

Rhizoctonia bare …

Studies On Bean Yellow Mosaic Virus In Pasture Species And Lupins., Simon Mckirdy, R. Jones

Experimental Summaries - Plant Research

Trial 90PE11

Location: South Perth.

A survey was conducted to determine the extent of Bean Yellow Mosaic Virus (BYMV) infection in subterranean clover pastures. The pastures were sampled in October by officers from each of the country districts and from south Perth. 100 samples were collected from each pasture, 1 sample every 5 paces , and sent to south Perth. The ELISA test and the Gibbs and Gower formula were used to determine a percentage BYMV infection for each infected pasture.

Barley yellow dwarf virus in wheat

Location: Badgingarra, Wongan Hills, Goomalling-Dowerin, Northam, Katanning, Jerramungup.

In 1990, very large populations …